Bug

When switching from local to remote mode (triggered from mobile), the CLI exits instead of switching. The doSwitch callback correctly sets exitReason = { type: "switch" }, but the subsequent ExitCodeError catch block unconditionally overwrites it with { type: "exit", code: 143 }.

Steps to reproduce

1. Start happy CLI in local mode
2. From mobile app, trigger switch to remote mode (press space)
3. Expected: CLI switches to remote mode
4. Actual: CLI exits completely

Root cause

In the main session loop, when a switch is triggered:

1. doSwitch sets exitReason = { type: "switch" }
2. Claude process receives SIGTERM → exits with code 143
3. Catch block handles ExitCodeError(143)
4. Bug: catch block unconditionally sets exitReason = { type: "exit", code: 143 }, destroying the switch intent
5. Loop sees type === "exit" and terminates

Fix

Guard the ExitCodeError catch to preserve an existing switch intent:

  if (e instanceof ExitCodeError) {
    if (exitReason && exitReason.type === "switch") {
      break; // preserve switch intent — exit code 143 is expected from SIGTERM
    }
    session.client.closeClaudeSessionTurn("failed");
    exitReason = { type: "exit", code: e.exitCode };
    break;
  }

Confirmed with logging

Added debug logging to the catch block. On reproduction, logs show:

[local]: exitReason at catch time: {"type":"switch"}
[local]: ExitCodeError (code 143) but exitReason is already 'switch', preserving switch intent

With the guard in place, the switch completes successfully.

Environment

• happy 1.1.3 (npm global)
• Node.js v20.19.5
• Ubuntu 22.04, x86_64